


Long kept Secrets

by Vauvenal



Category: Undertale (Video Game)
Genre: Cunnilingus, F/M, Fingering, Plot What Plot/Porn Without Plot, Skeleton puns because I couldn't resist and it's Sans, no ghost dicks this time
Language: English
Status: Completed
Published: 2016-06-21
Updated: 2016-06-21
Packaged: 2018-07-16 10:25:12
Rating: Explicit
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 2,406
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/7264126
Author URL: https://archiveofourown.org/users/Vauvenal/pseuds/Vauvenal
Summary: <blockquote class="userstuff">
              <p>You've known each other for quite some time - and there are things needing to be said.</p><p>This was my first /Reader fic as well as my first Undertale fic ever, so bear with me. ;)</p>
            </blockquote>





	Long kept Secrets

It’s cold outside.  
Well, of course it is.  
It’s always cold in Snowdin, most likely that is how the small town got its name. Still, if one isn’t used to it like the monsters living there, it can get pretty uncomfortable.

You have spent quite some time in the underground by now, making friends, chatting with strangers and getting along with everyone, despite being obviously not a monster.  
Since you had no other place to go, Sans’ and Papyrus’ house is your home for the time being. You sleep on the couch, enjoy Papyrus’ (gradually improving) spaghetti and lead a nice life.  
A lot of things have changed since you moved in with the brothers. Not just the way you treat them, but also the way they – specifically speaking, Sans – treat you. Whenever Papyrus is out on patrol, calibrating his puzzles or enjoying another of Undyne’s extreme cooking lessons, his brother tries to get closer to you. Or is that just your mind playing tricks on you?  
Of course that must be it. There is no way Sans feels anything but friendship for you.  
Still … the longer you stay and the more time you spend together, the closer you grow. You feel yourself getting attached to him, laughing together with him, mocking each other for fun and occasionally having a nice movie night.

Ah yes, movie nights.

The perfect opportunity for maybe-hopefully-soon-to-be couples to get closer to each other. In Sans’ case, you find him being surprisingly blunt, if not clumsy when it comes to flirting. Starting from him stretching to “coincidentally” put an arm around your shoulders and ending at shy glances towards you, quickly turning back to the screen as soon as he notices you looking at him.  
Eventually, you sigh and chuckle.  
“You know Sans … you can stop playing around. I get it.”  
“Huh? What? You get what?” A blue glow spreads across his cheeks, apparently his way of blushing.  
You lean your head on his shoulder, snuggling into the furred rim of his hood a little. “It’s kind of obvious. You have a crush on me, don’t you?”  
“H-hey, don’t try to poke my funny bone.”  
“That was really one of your worse puns,” you tell him and laugh. “Because I can see right through you.”  
“… hey, making puns is my job, baby.”  
Now it’s his turn to laugh, although it sounds nervous and a little forced.  
“Sans …” You sigh and lay a hand on the back of his skull, feeling the smooth surface and making him shiver. “You like me. A lot. You’re not as good at hiding your feelings as you think you are.”  
He sighs and closes his eyes, taking a deep breath.  
“Okay. I like you. A lot. Satisfied?”  
“I want to hear all of it.”  
“Can I go back to skullking now?”  
“No.” Now the second of your hands is on the back of his spine, tracing the vertebrae of his neck with a fingertip and feeling the little bumps and nooks and crannies. “I want you to be honest with me. Come on.”  
He looks at you, his gaze meeting yours for a second, before you can feel his ribcage moving as he takes a deep breath. “… I have a crush on you. A big one. I got no idea how this happened and I don’t think I wanna know either. It’s just … the way you are. Heck, I don’t know how to explain, don’t make this so hard for me.” He groans and leans his head back, staring at the ceiling.  
“You don’t need to explain anything, Sans. Turn towards me and close your eyes.”  
Another deep breath and then he does as you told him. Slowly you move towards him to press a kiss on his teeth, and you feel him smile a little against your skin. “This is nice,” he mumbles and you feel a cool, skeletal hand in your hair, holding you against him. This time, he is the one to kiss you, as deeply as it’s possible for him. “Do you have any idea how often I thought about this? But I just didn’t have the guts to tell you,” he mumbles.  
You stare at him for a moment and then laugh. He always manages to sneak in a pun, no matter if fitting or not. “Well, now you told me. Do you feel better now?”  
Sans laughs hoarsely. “Yeah. You took a skele-ton of a weight off my shoulders.”

The rest of the night is spent laughing, joking and exchanging kisses. Later, you fall asleep in his arms, nestled against his soft sweater, his ribcage moving against yours in the deep, steady rhythm of sleep.

-

It only takes you two a few days until you see yourselves as an actual, steady couple. Everything just … fell into place that night. You still sleep on the sofa though, because you’ve never been to Sans’ room before and don’t want to intrude his personal space, but sooner or later, he takes care of that, too.

“Hey,” he starts slowly when you’re sitting in front of the TV together, cuddled up in a blanket and watching the afternoon show with Mettaton. “You wanna hang out at my room tonight?”  
His pronounciation makes clear what he means, but still, you ask cheekily: “Do you mean ‘hang out’ or 'hang out’?”  
The answer you get is a grin just as cheeky as your own, and a kiss on the cheek.  
“Does that mean you’d like to get boned by me?”  
“Oh, stop it Sans!” Although you wonder how on earth you’re supposed to have sex with a skeleton, you decide not to ask any further. After all, Sans has always been full of surprises …

-

The first of these surprises is how hurried he is to get to his room with you after him, closing the door behind you. Sans seems impatient, as if … as if he’s been waiting for this to happen for far too long, and you decide to put an end to that waiting. “Bed?”, you whisper, and Sans smiles at you. “Sure. Whatever floats your bone.”  
You pull him with you, flopping down on the bed with him above you. His jacket is open and you can see his ribs through the shirt underneath. He’s holding himself up with his hands left and right of your head and – wait. Was that … a flash of blue in his left eye?  
You flinch for a second, as some kind of distant memory grazes your mind, but then it’s gone. “Stay calm. I won’t hurt you.”  
He nuzzles your cheek and whispers hoarsely into your ear, breath ghosting over your skin: “You’re gonna be mine tonight. I got a few more tricks up my sleeve, just for you.”  
Suddenly, you feel something wet trailing along your earlobe, and you shiver. It feels odd, a little like a tongue, but a bit cooler and slicker. As Sans raises himself again, you can see what it was: He does have a tongue. Pointed, longer than a normal tongue and emitting a soft, light-blue glow, not unlike to the flash in his eye you’d just seen. “What game are you playing here?” you ask and raise your arm to caress his cheek, but he gently pushes it back down by the wrist.  
“You’ll see soon enough. For now … just enjoy. I’m gonna make you weak in the knees.”  
A heavy weight seems to push down on your chest. Not enough to hurt you or restrict your breathing, but enough to keep you in place. Sans’ eye is glowing a little brighter, and now you can fully see the blue tint. For a second, the wave of fear rushes over you again, but as Sans nuzzles you and kisses your cheek, you feel calm again.  
He smiles at you, tongue showing, a silent promise of what he’s planning. But first things first, he gently pushes up your shirt, all the while caressing every inch of visible skin until he reaches your chest, shoving the cups of your bra aside. “Let’s see what I can do with these.” You watch him as he bows his head to lick at one nipple, coating it in saliva, gently pinching the other one. Soon enough, your breathing gets heavy and audible, gasps and silent moans escaping your lips as he makes sure to make you feel as good as possible. Almost without noticing, you raise one of your legs, putting the heel of your bare foot on Sans’ tailbone, stroking up and down. He groans against your skin. “S-stop that …”  
“Why should I?”  
He chuckles softly. “'cause this is about you and not me.”  
You respond with another breathless laugh. “If you say so …” But you’ll definitely keep that spot in mind for later.  
“I want to see you completely. Like … all of you.”  
You understand that there’s a hidden plea in his words. “Can you get off me? Just for a moment?”  
“Hmm … nah, I think I’ll take care of that myself.” Sans grins at you, eye glowing with want and then pulls down your pajama pants and your underwear at once. He shudders as he sees you like this, naked, being held down by his magic and so, so wet. You look up to him, watching his movements, his expression, his hands stroking up and down your sides. Eventually, he cups both of your breasts with his bony fingers, cool, smooth and hard against your skin. He rubs your nipples with his thumbs, making you cry out in lust. “Shh, girl, not so loud.”  
“I-I’ll try, but you’re really good at th- oh, fuck, yes.”  
You cry out again as you feel one of his legs being pushed against your crotch, his kneecap hitting your clit, giving you something to grind against while he still takes care of your nipples, his hands slowly warming up, massaging and caressing you at the same time.  
“Does someone there want more?”  
Cringing at the taunt, you bite your lower lip and try to think of a witty answer, but you’ve lost any kind of concentration and can only nod at his question which makes him lick his way down your body, tracing your nipples, the outline of your breasts and down your stomach. His tongue leaves behind a thin trail of saliva and goosebumps all over you. Soon, but not too soon, he lets go of your nipples and instead uses his hands to gently spread your legs, giving him a better view of your almost dripping wet cunt. He nuzzles your hip and breathes deeply, the cool air and arousing contrast to your body that feels like it’s burning in anticipation. “I’m gonna fuck you until your worn to the bone down here, girl …”  
Finally, he gives in and relieves you of your almost painfully arousing tension, licking the whole length of your cunt a few times. His tongue is much more agile than anything you’ve ever felt before, teasing you in all the right spots. The tip is now pushing against the underside of your clit, driving you mad with pleasure, his hands still all over your body, wherever they can reach. You can hear your own blood pounding in your ears as he touches your hole with his tongue. As you look down to watch him, you can see that his eye is glowing brighter, his expression a weird mix between adoration and pure lust. Then, he closes his eyes to focus all of his attention on pleasuring you, tongue intruding and feeling your insides. It’s squirming inside you, making you moan out loudly without any control – but Sans doesn’t seem to care anymore, either, for he is too busy pushing his tongue as deep inside you as he can, even touching the most intimate of places. He swirls the tip of his tongue around it, probing against that wonderful spot so deep inside you. Your arms and legs quiver and eventually, you can’t hold back and wrap your legs around his head.  
“S-sans, god, please don’t stop …”  
He purrs deeply against your crotch, sending pleasuring vibrations throughout your whole body. His hands trail down your body again and you feel a finger at your entrance, just next to the tongue. Carefully, he pushes your legs aside, giving you a break from the wonderful torture of his tongue, and licks his lips. “Ready for round 2?”  
You only shudder and buck your hips, trying to force his finger inside you. “Come on … please …”  
“That sounds like a nice girl. Then I should be nice too, hm?”  
He shoves two fingers inside you, their bumpy structure feels insanely wonderful against your insides. As he starts thrusting, they tease your entrance which is already red and overstimulated. It’s driving you crazy and you love it, you hear your own voice begging for more. The pressure on your chest gets stronger, maybe it’s his magic or maybe it’s you being left breathless because of him. Whatever it is, it makes your moaning and screaming and begging even more intense. A third finger is being pushed into you, each of them is moving individually, crooking, stretching, tickling and you hear his greedy, satisfied laugh through the haze of arousal that’s building around your thoughts. The only thing you can say for sure is that you’re moaning his name, again and again, like a mantra, Sans, Sans, Sans, yes, please, oh god so good, Sans!  
He crooks all three of his fingers and pushes his thumb against your clit, rubbing it and your insides in an unforgiving rhythm until you can’t take it anymore. You claw at his bedsheets to find something to hold onto as you buck against his hand a few more times, coming with a scream and covering his hand in a mixture of your fluid and his saliva.  
Very gently, Sans removes his fingers and flops down beside you.  
“Hey there, beautiful.”  
“Hey there, you gorgeous asshole,” you answer hoarsely. “You do realize I probably won’t be moving for a while?”  
“I told you I’d fuck you until you’re weak in the knees.” He licks his lips seductively and you shudder. “Did I make it or should I try again?”  
“… I swear to god Sans, if you touch me now, we’re not going to leave the bed until tomorrow.”

Only after saying this, you realize that this will be a very busy night.


End file.
